PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: See Disease Characteristics At least 4 weeks since prior chemotherapy (6 weeks for mitomycin or nitrosourea) and recovered No prior topotecan or other topoisomerase-I inhibitor No other concurrent cytotoxic therapy for ovarian cancer Endocrine therapy: No concurrent hormonal therapy for ovarian cancer Radiotherapy: See Disease Characteristics Recovered from prior radiotherapy At least 4 weeks since prior radiotherapy to area comprising at least 25% of bone marrow stores Surgery: At least 4 weeks since prior major surgery and recovered Other: At least 30 days since prior investigational agent or new anticancer therapy No other concurrent investigational therapy